Polishing machine



Nov. 16 1926. 1,606,925

c: s. CUSHMAN POLISHING MACHINE F iled Sept. 11, 1924 I zz means learnerearner.

CHARLES S. GUSHLESQI, F VERIJEONT.

POLISHING IEACHINE.

Application filed September 11, 1924.

This invention relates to new and useful improvements in stone working machines, and particularly to devices for polishing stone.

' In the type of polishing devices disclosed in my Patent 1,491,790, issued to me April- 29, 1924, there is a tendency for the motor to rotate on the polishing element, due to the fact that the weight of the device produces great friction between the polishing element and the stone to be polished. It is, therefore, the principal object of the present invention to take advantage of this rotating tendency as means for automatically elevating the polisher to such a position as will permit the polishing element to rotate and, at the same time, be maintained in proper polishing contact with the surface to be polished.

Another object is to so suspend the polishing device so that it may readily be moved back and forth over the surface of the stone, and yet maintain in a horizontal plane, and in proper contact, at all points, with the surface thereof.

Other objects and advantages will be apparent from the following description when taken in connection with the accompanying drawings.

In the drawings:

Figure 1 is an elevation of a polishing device showing the elevating and lowering device associated therewith, which forms the subject matter of this application, the parts being in the position assumed when idle, the casing being broken away.

Figure 2 is a horizontal sectional view on the line 2-2 of Figure 1.

Figure 3 is a horizontal sectional view on the line 33 of Figure 1.

Referring particularly to the accompanying drawing, 10 represents the motor, the shaft 12, of which has a gear 13 meshing with a ring gear 14. To this ring gear is connected the polishing element 15, which contacts with, and polishes the face of the stone 16. On the upper side of the motor casing there is formed vertical post 17, and carried by the upper end of this post is a universal joint 18. To provide suspending means for the polishing apparatus are the horizontal parallel bars 19, connected pivotally at their intermediate portions to the universal joint, and disposed through the ends of these bars, to hold the latter in parallel spaced relation, are the bolts 20.

III

Serial No. 737,116.

Mounted at a suitable height above the stone 16 is a horizontal track 21 on which is sup ported the wheeled carriage 22. Connected to the ends of the carriage 22, are the vertical parallel cables 23, spacer bars 24 being disposed between and connected to these cables, at regularly spaced intervals. Enclosing the motor and the gear mechanism of the device is a casing 11, having a circumscribing and spaced handrail 25, which is adapted to be grasped by the operator to manipulate the polisher back and forth across the face of the stone, while at the same time the polisher performs a continuous rotary movement in a horizontal plane, on the surface to be polished. The universal joint 18 permits the polishing device to maintain its position with the polishing element in a horizontal plane, while the device is swung forwardly, backwardly and laterally across the stone, thereby preventing one side of the said element from rising higher than the other side.

Before the motor is started, the entire weight of the polishing apparatus rests on the surface of the stone 16. When the motor is started, the great frictional engagement between the element 15 and the stone, holds the former stationary and causes the motor to rotate on the said element. As the motor rotates, the post 17 causes the parallel bars 19 to swing arount in a horizontal plate, carrying the attached ends of the cables with them, with the result that the cables are given a twisting movement with relation to each other, thus shortening the suspending means. The spacer bars 24, however, prevent actual contact of the cables with each other. As this twisting movement continues, the entire polishing mechanism will be elevated, and such a height attained that the frictional contact between the element 15 and the stone will be reduced, whereupon the element will rotate on the surface of the stone, with the proper degree of pressure to polish the surface thereof.

It will thus be seen that, while the motor is in operation, the polishing element will be maintained in proper contact with the stone, and should the pressure of the polishing element upon the stone, for any reason, be increased, twisting action of the cables will immediately take place to elevate the device to the proper height to insure the desired contact with the stone.

The carriage permits the polisher to be moved longitudinallyof the stone, so that action can be'brought to bear on different parts of its surface.

The track 21 is suspended by the cables 26 which pass over the pulleys 2'? and are connected to a winding drum 28. The ends of the track are connected with uprights 29 for vertical sliding movement, upon rotation of the winding drum, so that stones of dilferent thicknesses may be accommodated.

Suspended on the center of the carriage is a chain hoist 30, which includes the lifting chains 31, and the hand chain 32. lfhe lower ends of the lifting chains are provided with hooks 33. The ends f the lower bars 19 have rotatably supported therebetween the grooved wheels or pulleys 35, the lower end portions of the cables 23 being engaged in said pulleys and directed up wardlygwhere they are formed with loops 3-1 and 36 to receive the hooks 33, of the lifting chains. The bars 24: are spaced from the cables to a suiiicient distance to permit the free movement of the lifting chains 81. This construction per iits the cables 23 to be adjusted to suit the operator, and the character,- or thickness of the stone being polished.

lVhat is claimed is:

1. A polishing device comprising, in combination withan elevated support, of a motor driven polishing element, means between the support and said polishing element adapted to suspend the latter while operable to permit the weight of the element to rest upon a surface to be polished, said suspending means being adapted to twist upon reaction f the motor to the resistance resulting from the frictional contact of said element with the surface to be polished, whereby to tend to elevate said element into the proper polishing contactual pressure against said surface. V

2. A polishing device comprising the combination with an elevated support, of a motor driven polishing element, a flexible twistable suspending means between the support and the motor driven element, said flexible element being adapted to be twisted by the motor of the element due to the resistance offered by thesurface to be polished to the polishing element, whereby said element will be raised from the surface to be polished to a sufficient degree to reduce the frictional driven polishing element, a flexible suspend:

(30 ing means between the track and elei'nent whereby said element iscapable of movecontact between the surface and said ele' ment to be positioned with reference to the surface to be polished, said flexible suspending means being adapted to be twisted by the motor of the motor drlven element due to the resistance offered by the surface to.

ible neans supporting the polishing element from the elevated support and operable by the reaction of the motor to the resistance to the rotation of the polishing element of fered by the surface to be polished whereby to lessen the pressure between the polishing element and the surface to be polished.

1 polishing device comprising a polelement, driving means for said pm the polishing element to restwith its full weight upon a surface to be polished but automatically operable byv said driving means to elevate said polishing element to a proper polishing pressure against said. sur- 6. in a polishing device, arotatable polishing element normally resting with its full weight on the surface to be polished, means for rotating said element and flexible suspending means for said elen'ient arranged to be twisted by said driving means when latter is initially set in motion whereby to tend to elevate the element to a degree suilicient to produce the proper polishing cont actual relation between the element and the surface to be polished.

7. in a polishing device, a rotatable polishing element, means for rotating said element, said element normally bearing on the surface to be polished with such pressure as to resist rotative action of the rotating means, flexible suspending means for said element arranged to be. twisted by said rotating means whereby to tend to elevate the element to a degree suilicient to reduce the pressure between the element and the surface to be polished, thereby permitting said element to be rotated by the rotating means, and means for adjusting the flexible ,suspending means whereby ,to regulate the height of the polishing element with respect to the surface to be polished.

in testimony whereof, I my signature.

CHARLES S. QUSl-il'iiiii ing eltinent, means operable to permit 

